A major hypothesis in the psychology of non-pathological human aging is that age-related declines observed in primary cognitive abilities can depend largely upon elderly people's failures to engage in adaptive problem-solving. A great deal of the releveant literature has focused on verbal learning, memory and attention; and these will here be the central priamry abilities under investigation. Young and elderly adult's appraoches to deploying their verbal- learning, memory and attentional skills will be compared in a series of 11 cross-sectional and longitudinal studies. The project's main aims are: (a) To establish solid measurement bases for interpreting age differences observed on specific tests of problem solving over a range to cognitive domains; (b) To test the short-term and long-term stability of individual differences in problem solving; (c) To test the generality of individual differences in these functions using six different problems that reflect Prose Comprehension and Memory, Associative Memory, Rote Memory, and Focus of Attention; (d) To use cognitive-strategy instruction to control memory strategies so as to amplify and elaborate potential differences in young vs. elderly adults' basis short-term and long-term (incidental) memory abilities; (e) In addition to these laboratory studies, all subjects will be given a preliminary interview that solicits information about demographics, health, and education; and they will be given the Wechsler Adult Intelligence Scale (WAIS), and the Short Inventory of Memory Experiences (SIME). The laboratory findings will be analysed relative to the interview information plus specific factor scores from the WAIS (Gf, Gc, SAR) and the SIME (Rote Memory Recent Memory) to determine the degree to which age-related deficits in problem solving and domain-specific performance are related to specific theoretical intelligences, recent domain- related experiences, health, and education.